Electrical devices and electrical systems often require the rectification of an alternating current (AC) input. Rectifier circuits can be used to supply electrical systems or electrical devices, such as appliances, with suitable rectified voltage and current. Rectification of an AC input is important in many common applications such as in industrial and consumer electronics and appliances, including for example, refrigerators with linear compressors, induction cooking appliances, HVAC compressors and heating elements.
In many applications, a common rectifier circuit for AC input rectification can utilize diodes and diode bridges for passive rectification. Although the use and implementation of diodes for passive rectification in diode bridge rectification circuits can be accomplished without the use of complex circuit topologies, such as in the half-bridge and full-bridge configurations, diode bridge rectification circuits or diode bridge rectifiers have disadvantages, namely diode conduction losses. Diodes can cause significant conduction losses in diode bridge rectifier circuits since forward voltage drop of a diode can be relatively high. For example, the conduction losses caused by diodes can result in poor power transfer efficiency percentage for a lower power application.
Active rectification can be used to reduce conduction losses and improve efficiency in AC rectification. Some active rectifiers provide improved efficiency over passive diode bridge rectifiers by reducing resistive losses in the rectifier by replacing diodes with MOSFETs. Conduction losses can be reduced because MOSFETs can have a low RDS on-resistance which results in lower conduction losses in a rectifier circuit. However, some systems and methods of active rectification require the use of microcontrollers to drive MOSFETs which can be undesirable because of increased cost or additional control loop.
Accordingly, systems and methods for providing self-driven active rectification utilizing streamlined and cost effective circuit topologies and control methods, which deliver reduced conduction losses, would be useful and welcomed.